412 HA WK 



value, but in other respects quite as important, that the sexes differ 

 very greatly in size, that in most species the irides are yellow, 

 deepening with age into orange or even red, and that the im- 

 mature plumage is almost invariably more or less striped or 

 mottled with heart-shaped spots beneath, while that of the adults 

 is generally much barred, though the old males have in many 

 instances the breast and belly quite free from markings. Nearly 

 all are of small or moderate size — the largest among them being 

 the Gos-Hawk and its immediate allies, and the male of the 

 smallest, Accijnter timis, is not bigger than a Song-THRUSH. They 

 are all birds of great boldness in attacking a quarry, but if foiled 

 in the first attempt they are apt to leave the pursuit. Thoroughly 

 arboreal in their habits, they seek their prey, chiefly consisting of 

 birds (though reptiles and small mammals are also taken), among 

 trees or bushes, patiently waiting for an unwary victim to shew 

 itself, and, when it appears, gliding upon it M'ith a rapid swoop, 

 clutching it in their talons, and bearing it away to eat it in some 

 convenient spot. 



It is impossible to enter into details of the numerous forms 

 which, notwithstanding the limitation above adopted, are to be 

 called Hawks, or to describe the distinguishing characters, so far 

 as any have been given, of the different groups or sections into 

 which it has pleased systematic ornithologists to break them up, 

 since hardly any two are agreed in the latter respect. There 

 is at the outset a difference of opinion as to the scientific name 

 which the most numerous and best known of these sections should 

 bear — some authors terming it Nisus, and others, who seem to 

 have the most justice on their side, Aceipiter. 



In a Avider sense the word. Hawk, includes a considerable 

 number of forms which cannot be positively assigned to any of the 



groups already named, one instance of which, 

 out of several that could be cited, is seen in 

 the Neotropical genus Harpagus, whose deeply 

 and doubly -notched bilP has caused it to be 

 often put in the subfamily Falconinm. But thei-e 

 ,.^^^I^^^^^' . its short and rounded wings, and the style of 



(After Swainson.) . . , i ■ i 



its successive plumages make it strangely out 

 of place, so that its true position must be regarded as undetermined. 

 The same characters, added to that afforded by its " amber " irides 

 {Proc. Zool. Soc. 1882, p. 623), indicates that the rare form which 

 had the misfortune to be named Spiziapteiiix {Ibis, 1862, pi. ii.) is 

 a near ally of Harpagus, notwithstanding all that has been said to 

 the contrary. One species of Harpagus is subject to Mimicry. 



' The " donticulations " are not merely superficial, as is the case with many 

 birds possessing them, but exist, as Mr. Ridgway has shewn {Bull. If. S. Oeol. 

 and Geogr. Survey, ser. 2, no. 4, pi. xii. fig. 8), in the bone of the premaxilla. 



